The use of rechargeable batteries and rechargeable battery-operated devices is well-known. Many rechargeable devices utilize independent recharging modules which can be separate from the device, which is plugged into the recharger module. Other devices utilize an external device, such as a transformer with charging circuitry, plugged into the wall and connected to the deiice to be recharged either through a cable or through some type of an external recharging stand. Other devices using rechargeable batteries are self-contained and include various mechanisms for directly connecting the device to a recharging source, such as a standard a.c. outlet. Two examples of such devices are shown in Bohnstedt, et al. U.S. Pat. No. 3,458,794, issued July 29, 1969, and in Fenne, et al. U.S. Pat. No. 4,647,832, issued Mar. 3, 1987.
In self-contained devices, an appropriate connector, such as a plug having a pair of electrical plug blades or prongs, is adapted to be extended from the device so that the plug blades can be received in an electric outlet or other source of energy. When charging is completed, the prongs are suitably retracted or withdrawn into the device.
For example, the recharging connector or plug blades may be rotatably mounted within the device. The recharging connector may be suitably manipulated so that the blades are rotated to extend out from one surface thereof in position to be inserted into a standard electrical outlet, if that be the nature of the power source, and, alternatively, can be rotated into a position within the housing of the device for storage and operation of the device.
In such self-contained rechargeable devices, when the blades are positioned for connection to a recharging source, i.e., are in the recharging position, the recharging connectors, e.g., the plug blades, normally operate to connect the recharging source to an electric circuit for recharging the batteries. The recharging connector is often disconnected from the recharging circuit when the blades are retracted or positioned into the standby or non-recharging position. In this way, inadvertent connection of the power source to the blades, e.g., when a device or load is connected to the rechargeable batteries, is precluded.
In Fenne, et al U.S. Pat. No. 4,647,832 identified above, and assigned to the assignee of this application, there is disclosed a three-position switch for a portable, rechargeable device, such as a rechargeable flashlight. In the device disclosed in the Fenne, et al. patent, a slide interacts with a rotatable, connector to effect rotation thereof into an extended or charging position. In this position, the connector is connected to a recharging circuit, which is connected to the battery. The slide is also operative to effect repositioning of the recharging connector into a retracted or standby position in which the connector is disconnected from the recharging circuit. Additional operation of the slide effectuates a connection between the batteries and the load, e.g., a light bulb, to energize the load.
The highly successful device embodying the disclosure of the Fenne, et al. patent utilizes a pair of slide contacts connected to the slide for completing the circuit between the rechargeable batteries and the load, or light bulb, for energization thereof when the slide is moved into the "on" position. As shown in the Fenne, et al. patent, two slide contacts are carried by the slide member to complete the circuit between the battery and the light bulb.
While the structure embodied in the Fenne, et al. patent has been highly successful, there is a desire and need to provide for a self-contained, electrically-operated device utilizing rechargeable batteries which can be constructed less expensively with a minimum of components. In conjuntion therewith, it is highly desirable in such electrical devices to ensure that during recharging there is no connection between the battery and the load to prevent inadvertent operation thereof, such as from the source of recharging energy, and also to ensure that when the device is to be operated, the proper connections are made between the battery and the load.
While necessary circuit elements, connectors, and conductors are required, it would be desirable to minimize the number of these components, to construct them of standard materials, to utilize as much as possible electrical connections for multiple purposes without sacrificing and diminishing safety, and to do this all within a self-contained unit providing for reliable operation and rechargeability.